2) Choose the web application (where you are going to
create the site collection) from the drop down. Make sure all existing databases
show the status as Stopped. If not
click on the database that is in Started
state and change the Database status to Offline. Click OK

3) Back to Content Databases page (CNTDBADM.aspx). Click
on Add a content database

4) Enter the details: Database Server, Database Name .Click
OK

5) The new content database would be listed in your
Content Database page and status would be Started